macrumors 68000

Are you using your ISP's SMTP server? If so, usually you have to be using your ISP internet connection otherwise it will reject the connection (unless the SMTP server has username/password authentication). If you're using mobile broadband it might see the request coming from outside their network and reject accordingly.

If this is the case you might want to check if your ISP's SMTP server supports authentication or else find a universal SMTP server you can use instead.

I think the reason is to stop spammers using the server, only the ISP's customers can send through it.

macrumors G4

I have been using for outlook 2011 without any dramas until yesterday when i got a new mobile broadband ISP (Telstra). I can receive emails fine but when I try to send any I get the following error:

"Outlook cannot connect to the server. Verify that your computer is connected to the network."

But as soon as I disconnect the mobile broadband and connect to any available wireless connection the email sends fine.

I spoke to my ISP and they have no idea, because they don't support outlook 2011.

Any ideas?

Click to expand...

NATO is correct. You have encountered an almost universal security measure to prevent the use of SMTP servers as SPAM relays by foreign email accounts. It has nothing to do with firewalls. At any rate, you are probably trying to use unsecured SMTP on Port 25. In many cases, changing to authenticated SMTP on Port 587 will do the trick. There other secure SMTP ports, but 587 is most common and the one that you should try first.

macrumors G5

NATO is correct. You have encountered an almost universal security measure to prevent the use of SMTP servers as SPAM relays by foreign email accounts. It has nothing to do with firewalls. At any rate, you are probably trying to use unsecured SMTP on Port 25. In many cases, changing to authenticated SMTP on Port 587 will do the trick. There other secure SMTP ports, but 587 is most common and the one that you should try first.

macrumors G5

The known issues with Office 2011 for Mac are endless. According to both VM and MS, port 465 should work for outgoing mail....But it won't plenty of people having the same problem, so guess it is an MS issue.

Thunderbird works perfectly, so I paid the extra for a product that doesn't work!

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